Record disk



that they tend to warp out of shape.

Patented Feb.A 3, 1942 UNITE-D STATES PATENT orifice Binding Corporation, C

tion of Delaware.

hlcago, lll., a corpora-` Appueeiien Mai-en 11, 1940, Serin No. 323,438

.s claims. (ci. zii-'42) thin sheet, which may be paper or the like, covered by a layer of plastic material upon which an impression or sound track may be made. 'Ihis type of record can be made exceedingly cleaply,

and is particularly adapted for home recordingy purposes.

Phonograph disk records of the type comprising a paper'or cardboard base overlaid by a layer of plastic material are subject to the objection This interferes with the proper recording of sound on the record, if the warping takes place before the sound is recorded, and interferes with the reproduction of the sound thereafter. It is one of the objects of the present invention to provide aL disk record of theabove type which will be so constructed as to inhibitl the tendency of' 'the same to Warp. In Iaccordance with the principles` Aof, the present'invention a circular disk record is reenforced` along the rim and at thecenter thereof. The base of the record may be made of In fact it may be made ofl any material whichv has the necessary strength but lacks the characteristios necessary for receivinga sound track or record. The center portion of the record, which is the part upon which no sound track is t0 bel made, and the outer rim of the record, are of greater thicknessthan the intermediate portion. The intermediate porticn'is thus recessed to form an annulus between the rim and the center portion. This recess is preferably made exceedingly shallow. lIt may be of the order of a fraction of a hundredth of an inch, ror it may be of a greater depth, namely, a depth of one or more hundredths of an inch, or even one or more tenths of an inch. In this depressed annulus I mount a similar annular sheet upon which the sound record is tobe formed. 'I'his annular sheet is ,preferably `of a thickness approximately 'equal 'and' preferably not exceeding the depth of the ,f annulus in the base or foundation of the record.

illls the annular depression in the foundation sheet so that at its outermost edge the adhered sheet is ush with the rim on the record, and at its inner edge the adhered sheet is flush with the inner raisedpart of the foundation sheet. If desired, the rim may be so much thicker than the depressed part for receiving the sound track material that the rim extends as a peripheral flange around the iinishedrecord. The rim on the foundation sheet, as well as the inner thickened part of the foundation sheet, is preferably highly compressed so as to be of greater strength than the rest of the sheet. It may be coated with a'waterproof film whichv may be of plasticmaterial, varnish, shellac, or 'the like or, if desired, the covering lm may be a plastic material such as is used for the recording film.

The recording film hereinabove mentioned may 4be made of any desired plastic material such as,v

for instance, nitrocellulose. cellulose acetate,

' ethyl cellulose, or the vinyl types of plastic'. The.

above'are merely ay few of the plastic mterials suitable for receiving a record'of sounds capable ofiy reproduction.

While I have here spoken of the record film or sheet as being applied within the groove in the foundation sheet by pasting, or adhering the same, in position, itmay be applied otherwise.

For instance, the foundation sheet with its annular depression `may be dipped in a vat or-the like containing the plastic and then smoothedv so that the plastic fills the annular depression in the foundation sheet and may or may not also overlie the rim and all or part of the inner thickened portion ofthe foundation sheet..

The attainment ofthe above and further objects of the present invention will be apparent from the following specification taken in con- This annular sheet may be made of plastic ma- This sheet is pasted or otherwise adn herably securedto the foundation or baseof thev reeordw1th the plastic side of the sheet outermost. This sheet preferably, but'not necessarily,

structions; and

junction with the accompanying drawing forming a part` thereof.

lIn the drawing: Figure 1- is a plan viewof a foundation disk for a record embodying the present invention;

Figure 2 is a plan view of a recording film to be applied to the disk of .Figure l;

Figure 3 is a sectional view, on a very much enlarged scale, of a phonograph record formed by assembling the film of Figure 2.on .the disk of Figure l; Figures 4, 5 and 6 are sectional views corresponding to'Figure 3 and showing modified con- Figure 7 is a diagrammatic Vrview illustrating the manner of coating the ord of Figure 6.

disk vto form the rec- Referring now more particularly to Figures 1. 2 and 3, the phonograph record comprises -a foundation disk I overlaid by a recording film 2. The foundation disk is prefer'ably made of pressed paper pulp or papier-mch, although it may be made of other materials such as, for instance, of Bakelite or other molded material, of wood, metal, or of plastic material. In fact, it may be made of any material which has the' necessary strength but lacks the characteristics required for receiving a sound track or record. The material is depressed on each side to form an annular depression 3 which extends from the elevated center portion 4 to an outer rim 5. 'I'he outer rim may be of a width of approximately one-fourth of an inch, although this may be increased or4 decreased as is necessary to afford the requisite strength. -The outer r-im 5 is preferably compressed more compactly than is the intermediate part 3 of the disk whereby the rim l tends to impart the necessary strength to the foundation disk to prevent warping of the same. 'Ihe center portion 4 may be more compactiyy compressed than the intermediate part 3. If desired the foundation disk may be coated or sprayed with a strengthening or stiffening ma.

terial. This may comprise a coating of plastic orI Bakelite, or it may evenvbe a thin film of metal. 'I'he annular groove 3 is ma'de very shallow, of a depth only sufficient to receive a recording film 2. In one preferred construction the rim 5 and central part 4 were of a thickness of the order of 0.050 inch and each groove 3 was of a depth of 0.006 inch. This left the central part I of a depth of the. order of 0.038 inch. The film 2 is of an annular'shape having a central circular opening 8 of a .diameter equal to the diameter of the central portion 4 of the foundation disk I. The outside diameter ofthe film 2 is equal to the outside diameter of the depressed central annular part 3. The annular film 2 thus nfits into -and fills the depressed part 3 of the foundation disk I., The film 2 is preferably of a thickness approximately equal to the depth of the depressed part 3 of the foundation disc so that in the finished record the top surface of the recording film 2 lies flush with the adjacent surface of the rim 5. The film 2 is made of any material suitable for receiving a sound record .pasted or cemented' in place in the annular groove 3 of the foundation disk.

If desired, the entire exposed surface of th'e' foundation disk may be coated with the plastic material used for the sound record. 'I'his is illustrated in Figure 6 wherein the layer. I4 of the i plastic material extends overand around the Aedges of the foundation disk, as indicated at I8,

and over the center part 4 of the disk as indicated at I9. This also protects the edge of the disk from atmospheric moisture.

One method of coating the foundation disk to produce a record such as is illustrated in Figure 6 is shown diagrammatically `in Figure 7. In this figure the foundation disk I is mounted on a rotatable shaft andA is dipped into a tray 20 containing the liquid plastic which is to be coated onto the disk. The disk is then rotated through the tray, thus coating the entire disk withthe embossed at the center and at the outer periph- .1. A disk type phonograph record of uniform thickness comprising a base sheet of pressed paper pulp of the same thickness at the center If desired, the film 2 may be backed by la thin pasted, cemented, or otherwise adhered in the annular depression 3 in the foundationy disk I.

If desired, the plastic sound track receiving material 2 may coat the entire outside surface of the foundation record. The plastic sound recording surface may be painted or spread over the foundation record I, as illustrated in Figure 5. 'I'his leaves a very thin film I4 overlying the rim 5 of the foundation disk, and a thicker film I5 integral with the film I4, and filling the annular depression 'I in the foundation disc. The film I4 is generally, although not necessarily. too thin for receiving the sound record `and is relied upon only to act as a preserving layer over the rim 5 of the foundation disk.

and along the outer periphery and of a lesser thickness at the intermediate portion, and an annular layer of sound track forming material on said base sheet between the rim and the center portion and building up said intermediate portion to at least the same thickness as the rim and the center portion.

2. A disk type phonograph record of uniform thickness comprising a base sheet of pressed paper pulp of the same thickness at the center and along the outer periphery and of a lesser thickness at the intermediate portion, an annular layer of sound 'track forming material on said base sheet between the rim and the center portion and building up said intermediate portion to at least the same thickness as the rim and the centerportion, and a sealing coating of nonhygroscopic material covering the base sheet outside `said sound track forming material to prevent absorption of atmospheric moisture by the base sheet.

3. A disk type phonograph record comprising a circular base of paper stock material having an annular depression therein, an annular film of sound track receiving material,v a backing for said film, said film and backing being in and sub stantially filling said depression and said film serving to protect the subjacent part of the bas from atmospheric moisture. Y

4. A disk type phonograph record of uniform thickness comprising a -base sheet of paper stock 5. A disk type phonographic record of uniform l0 thickness comprising a base sheet of paper stock having an annular depression therein between the rim and the `center-thereof and of Luniform thickness from the center of the rim to 'the dey pression, an annular layer of non-hygroscopic plastic sound track forming material on said base sheetiin and filling said depression, said sound track `forming material serving to seal the subjacent paper sheet from .atmospheric moisture.

ISIDORE SPINNER. 

